Sugar Interaction Research Articles

Interactions of sugar alcohol, di-saccharides and polysaccharides with polysorbate 80 as surfactant in the stabilization of foams

The interaction of different sugars with polysorbate 80 as a surfactant at foam bubble interfaces was investigated with regard to the creation of stable foams. Sorbitol, maltose, sucrose and maltodextrin DE6 were applied at concentrations of 10–60% wt. Added sugars generally resulted in a lower foam overrun, but a narrower bubble size distribution and less drainage, especially at higher viscosities. The specific overrun, however, was found to strongly depend on the type of sugar used. Sorbitol enhanced the properties of polysorbate 80 as surfactant in terms of achievable overrun. Except for sucrose, higher sugar contents close to saturation were able to minimize detectable drainage after foaming. This effect was found to depend on interactions between polysorbate 80 as surfactant with sucrose or maltodextrin as viscosity builder, which could be indirectly assessed by comparing macroscopic foam property data. Sorbitol and maltodextrin led to the most homogeneous bubble size distribution and thus, helped to create the most stable foams. According to our findings, the functions of increasing viscosity by sugars and the interfacial activity of polysorbate 80 seem to overlap or to partially compete. This knowledge is of relevance for formulating foams with the highest level of robustness, e.g. for drying processes like foam-mat or vacuum drying.

Appetite-Regulating Hormones Are Reduced After Oral Sucrose vs Glucose: Influence of Obesity, Insulin Resistance, and Sex.

Fructose compared to glucose has adverse effects on metabolic function, but endocrine responses to oral sucrose vs glucose is not well understood. We investigated how oral sucrose vs glucose affected appetite-regulating hormones, and how biological factors (body mass index [BMI], insulin sensitivity, sex) influence endocrine responses to these 2 types of sugar. Sixty-nine adults (29 men; 23.22 ± 3.74 years; BMI 27.03 ± 4.96 kg/m2) completed the study. On 2 occasions, participants consumed 300-mL drinks containing 75 g of glucose or sucrose. Blood was sampled at baseline, 10, 35, and 120 minutes post drink for plasma glucose, insulin, glucagon-like peptide (GLP-1)(7-36), peptide YY (PYY)total, and acyl-ghrelin measures. Hormone levels were compared between conditions using a linear mixed model. Interaction models were performed, and results were stratified to assess how biological factors influence endocrine responses. Sucrose vs glucose ingestion provoked a less robust rise in glucose (P < .001), insulin (P < .001), GLP-1 (P < .001), and PYY (P = .02), whereas acyl-ghrelin suppression was similar between the sugars. We found BMI status by sugar interactions for glucose (P = .01) and PYY (P = .03); obese individuals had smaller increases in glucose and PYY levels after consuming sucrose vs glucose. There were interactions between insulin sensitivity and sugar for glucose (P = .003) and insulin (P = .04), and a sex by sugar interaction for GLP-1 (P = .01); men demonstrated smaller increases in GLP-1 in response to oral sucrose vs glucose. Sucrose is less efficient at signaling postprandial satiation than glucose, and biological factors influence differential hormone responses to sucrose vs glucose consumption.

Crystal structures of peanut lectin in the presence of synthetic β-N- and β-S-galactosides disclose evidence for the recognition of different glycomimetic ligands.

Carbohydrate-lectin interactions are involved in important cellular recognition processes, including viral and bacterial infections, inflammation and tumor metastasis. Hence, structural studies of lectin-synthetic glycan complexes are essential for understanding lectin-recognition processes and for the further design of promising chemotherapeutics that interfere with sugar-lectin interactions. Plant lectins are excellent models for the study of the molecular-recognition process. Among them, peanut lectin (PNA) is highly relevant in the field of glycobiology because of its specificity for β-galactosides, showing high affinity towards the Thomsen-Friedenreich antigen, a well known tumor-associated carbohydrate antigen. Given this specificity, PNA is one of the most frequently used molecular probes for the recognition of tumor cell-surface O-glycans. Thus, it has been extensively used in glycobiology for inhibition studies with a variety of β-galactoside and β-lactoside ligands. Here, crystal structures of PNA are reported in complex with six novel synthetic hydrolytically stable β-N- and β-S-galactosides. These complexes disclosed key molecular-binding interactions of the different sugars with PNA at the atomic level, revealing the roles of specific water molecules in protein-ligand recognition. Furthermore, binding-affinity studies by isothermal titration calorimetry showed dissociation-constant values in the micromolar range, as well as a positive multivalency effect in terms of affinity in the case of the divalent compounds. Taken together, this work provides a qualitative structural rationale for the upcoming synthesis of optimized glycoclusters designed for the study of lectin-mediated biological processes. The understanding of the recognition of β-N- and β-S-galactosides by PNA represents a benchmark in protein-carbohydrate interactions since they are novel synthetic ligands that do not belong to the family of O-linked glycosides.

Membrane-Sugar Interactions Probed by Low-Frequency Raman Spectroscopy: The Monolayer Adsorption Model.

Small sugars are known to stabilize biological membranes under extreme conditions of freezing and desiccation. The proposed mechanisms of stabilization suggest membrane-sugar interactions to be either attractive or repulsive. To obtain new insight into the problem, we use a recently developed low-frequency Raman scattering approach which allows detecting membrane mechanical vibrations. For model membranes of palmitoyl-oleoyl-glycero-phosphocholine (POPC) hydrated in aqueous sucrose and trehalose solutions, we studied the Raman peak between 12 and 15 cm-1 that is attributed to an eigenmode of the normal mechanical vibrations of a lipid monolayer. For both sugars, similar results were obtained. With an increase in sugar concentration in solution, the frequency position of the peak was found to decrease by ∼13% which was interpreted as a consequence of the membrane thickening due sugar monolayer adsorption on the membrane surface. The concentration dependence of the peak frequency position was satisfactorily described by a Langmuir monolayer adsorption model. It is concluded that, at small sugar concentrations (less than 0.2 M), the membrane-sugar interactions are attractive, while at higher concentrations (more than 0.4 M) the attraction disappears. The data obtained show that one sugar molecule on the surface interacts with approximately 3-4 polar lipid heads.

ADD Force Field for Sugars and Polyols: Predicting the Additivity of Protein-Osmolyte Interaction.

The protein–osmolyte interaction has been shown experimentally to follow an additive construct, where the individual osmolyte–backbone and osmolyte–side-chain interactions contribute to the overall conformational stability of proteins. Here, we computationally reconstruct this additive relation using molecular dynamics simulations, focusing on sugars and polyols, including sucrose and sorbitol, as model osmolytes. A new set of parameters (ADD) is developed for this purpose, using the individual Kirkwood–Buff integrals for sugar–backbone and sugar–side-chain interactions as target experimental data. We show that the ADD parameters can reproduce the additivity of protein–sugar interactions and correctly predict sucrose and sorbitol self-association and their interaction with water. The accurate description of the separate osmolyte–backbone and osmolyte–side-chain contributions also automatically translates into a good prediction of preferential exclusion from the surface of ribonuclease A and α-chymotrypsinogen A. The description of sugar polarity is improved compared to previous force fields, resulting in closer agreement with the experimental data and better compatibility with charged groups, such as the guanidinium moiety. The ADD parameters are developed in combination with the CHARMM36m force field for proteins, but good compatibility is also observed with the AMBER 99SB-ILDN and the OPLS-AA force fields. Overall, exploiting the additivity of protein–osmolyte interactions is a promising approach for the development of new force fields.

Short-Distance Intermolecular Correlations of Mono- and Disaccharides in Condensed Solutions: Bulky Character of Trehalose.

Organisms with tolerance to extreme environmental conditions (cryptobiosis) such as desiccation and freezing are known to accumulate stress proteins and/or sugars. Trehalose, a disaccharide, has received considerable attention in the context of cryptobiosis. It has already been shown to have the highest glass-transition temperature and different hydration properties from other mono- and disaccharides. In spite of the importance of understanding cryptobiosis by experimentally clarifying sugar–sugar interactions such as the clustering in concentrated sugar solutions, there is little direct experimental evidence of sugar solution structures formed by intermolecular interactions and/or correlation. Using a wide-angle X-ray scattering method with the real-space resolution from ∼3 to 120 Å, we clarified the characteristics of the structures of sugar solutions (glucose, fructose, mannose, sucrose, and trehalose), over a wide concentration range of 0.05–0.65 g/mL. At low concentrations, the second virial coefficients obtained indicated the repulsive intermolecular interactions for all sugars and also the differences among them depending on the type of sugar. In spite of the presence of such repulsive force, a short-range intermolecular correlation was found to appear at high concentrations for every sugar. The concentration dependence of the observed scattering data and p(r) functions clearly showed that trehalose prefers a more disordered arrangement in solution compared to other sugars, that is, bulky arrangement. The present findings will afford a new insight into the molecular mechanism of the protective functions of the sugars relevant to cryptobiosis, particularly that of trehalose.

3D Printed Sugar-Sensing Hydrogels.

The ability of boronic acids (BAs) to reversibly bind diols, such as sugars, has been widely studied in recent years. In solution, through the incorporation of additional fluorophores, the BA-sugar interaction can be monitored by changes in fluorescence. Ultimately, a practical realization of this technology requires a transition from solution-based methodologies. Herein, the first example of 3D-printed sugar-sensing hydrogels, achieved through the incorporation of a BA-fluorophore pair in a gelatin methacrylamide-based matrix is presented. Through optimization of monomeric cocktails, it is possible to use extrusion printing to generate structured porous hydrogels which show a measurable and reproducible linear fluorescence response to glucose and fructose up to 100 mm.

Glycation and Antioxidants: Hand in the Glove of Antiglycation and Natural Antioxidants.

The non-enzymatic interaction of sugar and protein resulting in the formation of advanced glycation end products responsible for cell signaling alterations ultimately leads to the human chronic disorders such as diabetes mellitus, cardiovascular diseases, cancer, etc. Studies suggest that AGEs upon interaction with receptors for advanced glycation end products (RAGE) result in the production of pro-inflammatory molecules and free radicals that exert altered gene expression effect. To date, many studies unveiled the potent role of synthetic and natural agents in inhibiting the glycation reaction at a lesser or greater extent. This review focuses on the hazards of glycation reaction and its inhibition by natural antioxidants, including polyphenols.

Insights into the chemosensory basis of flavor in table grapes.

The full flavor of grape berries is determined by the interaction of sugars, acids, volatile compounds, and other berry properties, such as astringency. Sugars and acids are important for berry taste, whereas volatile compounds are important for the unique berry flavors, e.g., monoterpenes for the Muscat varieties. We explored the basis for 'fruity' flavor perception in table grapes. Samples were collected from 134 new table grape lines and commercial varieties and tested chemically for their volatile profiles and organoleptically by tasting panels. At the sensory level, flavor impression was strongly correlated with berry preference, whereas among 'fruity', 'neutral', 'herbaceous,' and 'Muscat', only the 'fruity' flavor was correlated with berry preference. At the chemical level, 114 volatile compounds were detected in the 81 breeding lines and cultivars examined, and grouped into 'core' and 'unique' categories. The typical berry flavor seemed to depend on the major volatile aldehydes-1-hexanal and (E)-2-hexenal-accounting for up to an average 85% of the berry's core volatile concentration. We found four volatile compounds-α-bergamotene, geranyl formate, aristolene and α-penansinene-previously undetected, to our knowledge, in fresh grape berries. High 'fruity' flavor scores were related to three independent factors: (i) presence of unique volatile compounds, such as the sesquiterpene α-copaene, (ii) higher total concentration of volatile compounds, (iii) optimal maturity associated to high total soluble solids (TSS) levels, interacting with berry volatile composition. These combined sensory and analytical data on the flavor of table grapes improve our understanding of the complex interface between chemical and sensory perception in fruit. © 2019 Society of Chemical Industry.

Исследование физико-химических и текстурных свойств желированных десертов без желатина

The research features the technological challenge of producing jelly desserts by replacing gelatin by non-starch polysaccharides of plant, bacterial, and algal origin (separately or in binary mixtures) in order to overcome religious and ethical constraints. The authors focused on the texture which is responsible for gel network formation of desserts. Hydrocolloids are widely used in many food formulations to improve quality attributes and shelf-life. The polysaccharides under analysis included alginate, pectin, iota-carrageenan, konjac glucomannan, xanthan, and guar gum, separately or in binary mixtures. The experiment made it possible to determine polysaccharides and their optimal concentrations (konjac glucomannan 0.4 % : xanthan gum 0.6 %; locust bean gum 0.2 % : xanthan gum 0.8 %; iota-carrageenan 0.4 %) as gelling agents for the production of desserts without gelatin. Formation of a gel network in desserts occurs as a result of a complex interaction of hydrocolloids, milk fat, and sugar. Structure formation of jelly desserts with polysaccharides occurs already at 18 ± 2°C in 20–40 minutes. In contrast, the structure formation of the control sample occurred at 4 ± 2°C in 2–3 hours. Sensory evaluation of the products was conducted by panellists according to the following criteria: taste, colour, consistency, aroma, and appearance. The paper also describes an analysis of texture indicators. The shelf-life was assessed according to moisture content and water activity as 24 hours at 4 ± 2°C. Several economically-viable new formulations were identified: they successfully reproduced the essential attributes of well-established and widely-consumed traditional gelatin desserts.

Glycoconjugates coated gold nanorods based novel biosensor for optical detection and photothermal ablation of food borne bacteria

Foodborne bacterial species have been identified as the major cause in most of the severe pathogen related diseases. Conventional methods like plating and enzyme-linked immunosorbent assay (ELISA) are time overriding and laborious. Fast detection of bacterial species in food is a proximate obligation to guarantee food safety. Nanotechnology has emerged as a great field in case of rapid detection of pathogens in recent years. In the present work, gold nanorods, (AuNRs) based sensor was developed for swift and sensitive detection of foodborne bacteria. AuNRs has good electro-optical properties due to its Near-Infrared (NIR) absorption and scattering in surface plasmon resonance (SPR) wavelength regions. By exploiting the sugar based adhesion properties of bacteria, the sugar capped AuNRs can be used as potential nanobiosensor to detect the food borne bacteria. Polyethylene glycol (PEG) coated AuNRs were covalently functionalized with different types of amine terminated sugar using EDC coupling reaction. The sensitivity of synthesized nanobiosensor was probed by lectin binding assay and also with food borne bacteria (Escherichia coli) by using spectrophotometric and microscopic techniques. Pseudomonas aeruginosa was also used to probe the specificity of our synthesized biosensor through lectin-sugar interaction. Due to the specific interaction of sugar coated probe with foodborne bacteria, our nanoprobe has shown significant and selective photoablation of targeted bacteria. This nanorod based nanobiosensor can be an ideal candidate for optical detection and ablation of foodborne bacteria.

Spectroscopic FTIR and NMR study of the interactions of sugars with proteins.

FTIR and NMR spectra were measured in parallel for specific two-components mixtures of various proteins with different sugar molecules, such as arabinose, glucose, and sucrose. In the FTIR spectra of arabinose with some of these proteins, the bands assigned to the vibrational modes of the CH and COH groups disappeared, and new ones, related to an arabinose-protein CN mode, appeared. Similar changes were observed in the FTIR spectra of lyophilized mixtures of arabinose with different amino acids. In additional FTIR spectra, measured for other protein-sugar mixtures, the bands correlated to the ring modes of arabinose, in the range 1150-1000 cm-1, disappeared, and two new very strong narrow bands became dominant, indicating ring opening or some kind of arabinose decomposition. Contrary to the prevailing opinion that complexes between sugars and proteins are formed mainly by hydrogen bonds, the IR and NMR spectra of the sugar-protein mixtures studied here suggest that significant chemical reactions also take place between the interacting sugar and the protein. Two types of sugar-protein chemical reactions can be distinguished on the basis of these IR spectra, leading to the formation of a new CN bond and to the decomposition of sugar skeletal bonds. The new IR bands suggest that the latter reaction results in the formation of new bonds, which are related to new polyether moieties. These results highlight the often ignored non-specific chemical reactions that take place between sugars and proteins, and demonstrate that the simultaneous application of FTIR and NMR spectroscopic analyses can detect and further characterize these types of sugar-protein interactions.

КОНЕЧНЫЕ ПРОДУКТЫ ГЛИКИРОВАНИЯ И ИХ РЕЦЕПТОРЫ ПРИ СЕРДЕЧНО-СОСУДИСТЫХ ЗАБОЛЕВАНИЯХ

The advanced glycation end products (AGE) are a heterogeneous group of compounds formed by the interaction of sugars and active carbonyls with proteins and lipids. The purpose of this review is to discuss the role of AGE and their receptors (RAGE) in the pathogenesis and diagnosis of non-diabetic cardiovascular diseases. The new therapeutic approaches to the treatment of heart failure based on the regulation of the level of AGE and RAGE are considered.

Transcript profiling of carotenoid/apocarotenoid biosynthesis genes during corm development of saffron (Crocus sativus L.).

The dried stigmas of saffron constitute the world's costliest spice. Saffron has many therapeutic applications due to the presence of apocarotenoids. The latter are synthesized at different stages of development, and the biosynthetic pathway involves several genes encoding different enzymes. In order to understand the differential expression of various genes of the pathway, eight distinct developmental stages (S1-early to S8-late) were identified. The corms were assorted into three groups (I, II, and III) based on corm weight. Expression profiles of 12 carotenoid/apocarotenoid genes were studied. The expression of all genes was minimum/least in groups I and II corms during bud development. Lowest expression of carotenogenic genes (CsPSY, CsPDS, CsZDS, CsCRTISO, CsLYC-β1, CsLYC-ε, CsBCH2, and CsNCED) was observed during early stages (S1-S3) of corm growth (dormant period). In group III corms, increased expression of apocarotenoid genes (CsZCO, CsCCD2, CsUGT, and CsALDH) was observed during S4 to S8 stages (reproductive period, floral differentiation). Besides, expression profiles of genes in apical and axillary buds were also examined. Of all the genes studied, apocarotenoid biosynthesis genes (CsBCH2, CsZCO, CsCCD2, CsALDH, and CsUGT) were found to be upregulated in apical bud than in the axillary bud. The results indicated that interaction of phytohormones and sugars, mother corm reserves and the influence of internal and external factors may be contributing to the growth of saffron corm/bud. The study has laid a foundation for further research on the molecular mechanisms underlying bud dormancy/growth in saffron.

Studying glycobiology at the single-molecule level

Attempts to elucidate the roles of carbohydrate-associated structures in biology have led to the distinct field of glycobiology research. The focus of this field has been in understanding the evolution, biosynthesis and interactions of glycans, both individually and as components of larger biomolecules. However, as most approaches for studying glycans (including mass spectrometry and various binding assays) use ensemble measurements, they lack the precision required to uncover the discrete roles of glycoconjugates, which are often heterogeneous, in biomolecular processes. Single-molecule techniques can examine individual events within challenging mixtures, and they are beginning to be applied to glycobiology. For example, single-molecule force spectroscopy (SMFS) by atomic force microscopy (AFM) has enabled the molecular interactions of sugars to be studied, single-molecule fluorescence microscopy and spectroscopy have led to insight into the role of sugars in biological processes and nanopores have revealed interactions between polysaccharides and their transporters. Thus, single-molecule technology is becoming a valuable tool in glycoscience. Traditional approaches for studying glycans can lack the precision required to uncover their roles in biomolecular processes. Progress has been made in the use of single molecule techniques for examining individual events in glycobiology — such as the molecular interactions of sugars and their roles in biological processes — within challenging mixtures.

Influence of phenol and sugar interactions on antioxidant activity of pomegranate juice

Nowadays, people are focusing on antioxidant-rich food due to its beneficial effect on health. Thus, the goal of this study was to investigate the interactions between catechin, quercetin, and gallic acid in the presence of sugars (sucrose and trehalose) in complex food matrix such as pomegranate juice. Antioxidant activity (AOA) was measured by three different methods, DPPH and ABTS radical scavenging activity and ferric reducing antioxidant power (FRAP). In this paper, fundamental differences among used AOA measuring methods were confirmed, which can be traced back to interactions occurring between phenols and/or sugars. Even though addition of individual phenols increased AOA of mixtures, in the majority of binary and ternary mixtures antagonistic effects were observed. Positive effect of sugar addition was more pronounced in binary mixtures but the results were highly dependent on used AOA method.

Anapolar interaction of aminoacids and sugars in nonuniform magnetic fields

In the presence of a time-independent nonuniform magnetic field, represented by the axial vector $${{\varvec{B}}}$$ at the origin of the coordinate system and by the polar vector $${\varvec{C}}={\varvec{\nabla }}\times {\varvec{B}}^{\prime }$$ , assumed to be homogeneous, the l- $$\alpha $$ - aminoacids and d-sugars investigated in this paper carry an orbital electronic anapole, described by the polar vector $${\varvec{\mathcal {A}}}$$ . The electronic interaction energy of these molecules in nonordered media is a cross term, coupling $${{\varvec{B}}}$$ and $${{\varvec{C}}}$$ via $$\overline{a}$$ , one-third of the trace of the anapole magnetizability $$ a_{\alpha \beta } $$ tensor, i.e., $$ W^{\mathbf{BC}} = -\overline{a} {\varvec{B}}\cdot {\varvec{C}}$$ . Both $$\overline{a}$$ and $$ W^\mathbf{BC} $$ have opposite sign for two enantiomeric species, a fact quite important from the theoretical point of view. The magnitude of $$\overline{a}$$ predicted in the present computational investigation is very small, thus precluding the possibility of endogenous homochirality of terrestrial biochemistry. The possibility that powerful interstellar $${{\varvec{B}}}$$ and $${{\varvec{C}}}$$ may play a role on stereoselective chemical reactions and bias homochirality via anapolar interaction is also questioned, since the sign of $$ W^\mathbf{BC} $$ is not the same all over the series of l- $$ \alpha $$ -aminoacids and d-sugars.

Injectable Self-Healing Zwitterionic Hydrogels Based on Dynamic Benzoxaborole-Sugar Interactions with Tunable Mechanical Properties.

Dynamic hydrogels based on arylboronic esters have been considered as ideal platforms for biomedical applications given their self-healing and injectable characteristics. However, there still exist some critical issues that need to be addressed or improved, including hydrogel biocompatibility, physiological usability, and tunability of mechanical properties. Here, two kinds of phospholipid bioinspired MPC copolymers, one is zwitterionic copolymer (PMB) containing a fixed 15 mol % of benzoxaborole (pKa ≈ 7.2) groups and the other is zwitterionic glycopolymers (PMG) with varied ratios of sugar groups (20%, 50%, 80%), were synthesized respectively via one-pot facile reversible addition-fragmentation chain transfer (RAFT) polymerization. PMBG hydrogels were formed spontaneously after mixing 10 wt % of PMB and PMG copolymer solutions because of dynamic benzoxaborole-sugar interactions. The mechanical properties of nine hydrogels (3 × 3) with different sugar contents and pHs (7.4, 8.4, 9.4) were carefully studied by rheological measurements, and hydrogels with higher sugar content and higher pH were found to have higher strength. Moreover, similar to other arylboronic ester-based hydrogels, PMBG hydrogels possessed not only self-healing and injectable properties but also pH/sugar responsiveness. Additionally, in vitro cytotoxicity tests of gel extracts on both normal and cancer cells further confirmed the excellent biocompatibility of the hydrogels, which should be ascribed to the biomimetic nature of phosphorylcholine (PC) and sugar residues of the copolymers. Consequently, the zwitterionic dynamic hydrogels provide promising future for diverse biomedical applications.

Effect of sugars on the dynamics of hydrophilic fluorophores confined inside the water pool of anionic reverse micelle: A spectroscopic approach

In this article, we have investigated the structural and chemical effects of two sugar molecules, namely sucrose and sucralose on the structure of anionic reverse micelle (RM) AOT (aerosol-OT; sodium bis(2-ethylhexyl)sulfosuccinate)/n-heptane. The artificial sugar alternative sucralose shows very unique physical properties unlike other sugar molecules including sucrose and it is the reason behind choosing these two sugars in our study. The variation of shapes and sizes of the water pool of RM in presence of the two sugar molecules are investigated using dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS) measurements. It is observed that addition of both the sugar molecules swell the water pool of the RM and this enhancement is greater for sucralose. Moreover, we have employed time-correlated single photon counting (TCSPC) and fluorescence correlation spectroscopy (FCS) techniques for hydrophilic probes Coumarin 343(C343) and Rhodamine 6G (R6G) respectively inside the RM and we have observed that these two sugar molecules strongly retard the solvation and rotational dynamics of C343 and the translational diffusion of R6G inside the RM. Replacement of the smaller sized water molecules by the larger sized sugar molecules at the interface of RM through stronger hydrogen bonding with the interfacial sulfonate moiety of AOT increases the microviscosity and this may be the probable reason behind the slow dynamics of the probes in presence of sucrose. Along with this factor, strong electrostatic interaction of highly polar molecule sucralose with RM interface and with the dye molecules further retards the dynamics of fluorophores. Therefore, sucralose molecule exhibits its distinct feature by swelling the water pool inside the RM and slowing down the dynamics of the hydrophilic probes to a greater extent compared to sucrose which provides a new aspect of RM and sugar interaction.

Graphene oxide-based NIR fluorescence probe with aggregation-induced emission property for lectins detection and liver cells targeting

Probing lectin–sugar interactions is crucial to understand important biological process as well as develop clinical diagnostics and drug for the disease. Effective tools that target these interactions are thus in great demand. In this paper, two new aggregation-induced emission (AIE)-based glycosyl probes (PT-Man and PT-Gal) have been developed for the detection of lectin–sugar interactions in the near-infrared region (NIR). PT-Man and PT-Gal show significant fluorescence enhancement upon addition of a selective lectin with a relatively low detection limit. The fluorescence increment mechanism is ascribed to the aggregation of the AIE-based glycosyl probes after complexation with the selective lectin, which has been confirmed by the scanning electron microscope (SEM) measurement. Also, in order to further improve the sensitivity and selectivity of the probes, graphene oxide (GO) has been used as a platform to assemble with the two glycosyl probes. To our delight, the PT-Man@GO and PT-Gal@GO composites exhibit better sensitivity and selectivity for probing lectin–sugar interactions. In addition, due to the specific sugar-receptor interactions, the liver cancer cell line that over express the glycoprotein receptor can be specifically targeted by PT-Gal@GO.